Wheel raising and lowering mechanism for floor polishing machines and the like



April 13, 1954 INVHVTOR. DANIEL A.ARONES ATTORNEY Patented Apr. 13, 1954 WHEEL RAISING AND LOWERING MECH- ANISM FOR FLOOR POLISHING MACHINES AND THE LIKE Daniel A. Arones, Minneapolis, Minn., assignor to Advance Machine Company, Minneapolis, Minn., a corporation of Minnesota Application September 20, 1951, Serial No. 247,514

3 Claims.v (Cl. 280--44) My invention relates to an improvement in a wheel raising and lowering mechanism and more particularly to a type for use in a floor polishing machine or the like.

Floor machines are moved about the floor in operation and require a mechanism for lowering the wheels whereby the machine may be moved with the floor treating member raised from the floor to facilitate moving the same. To this end it is an object of my invention to provide a mechanism which raises and lowers the wheels of a floor polishing machine quickly and positively by a simple direct movement of the operators foot.

It is an additional object to provide a wheel raising and lowering mechanism which is virtually concealed within a portion of the floor machine housing and which is releasably held in a positive locked position when the wheels are in a lowered position. It is a further object to provide a pivoted cam arm and lever member which engages the shaft mounting the pair of running wheels of the floor machine and holds the wheel shaft in a positive lowered or raised position. It is also an object to provide a cam surface formed on the end and side of the pivoted cam arm member which is in direct contact with the shaft mounting the running wheels whereby an efiicient, simple and positive acting mechanism is formed for raising and lowering the wheels i of a floor machine or the like by acting upon the axle mounting the wheels of the machine.

The invention will appear more clearly from the following detailed description when taken in connection with the accompanying drawings, showing by way of example a preferred embodiment of the inventive idea.

In the drawings forming part of the application: I

Figure 1 is a side view of the main body portion of a floor polishing machine with my wheel raising and lowering mechanism holding the wheels in a lowered position.

Figure 2 is a bottom plan view of the machine and mechanism shown in Figure 1.

Figure 3 is a section on the line 33 of Figure 2.

Figure 4 is a section similar to that of Figure 3 but with the wheels in raised position.

Figure 5 is a section on the line 5-5 of Figure 2.

Figure 6 is a perspective view of the cam locking levers removed from the mechanism unit.

My wheel raising and lowering mechanism A is composed of the shaft ill on which are mounted the wheels II. The shaft H) in turn is mounted which the lever 2'! extends.

on the lower ends I 2 of the arms l3 and i3 which are pivotally secured to the stub shafts ll 4 mounted on the gear housing I 6 of the machine B. The housing It which mounts the motor cover member I! also conceals the wheel mechanism A and has formed inwardly thereof the inner depending wall members I8. Formed in each of the wall members I8 is a cutout recess I9 having the semi-circular corner portion 29 formed therein which aids in positioning the wheel axle H] as hereinafter described.

I further provide the shaft 2| which is rotatably mounted in the enlarged portions '22 formed in the inner walls l8. Secured to the ends of the shaft 2| are the pivoting cam locking members 23 and 24 which have formed on the lower depending ends thereof the semi-circular cutout portions 25 which engage the shaft 1 0 and place it in locked position when the wheels I! are in the lowered position shown particularly in Figures 1, 3 and 5. So that the cam locking members 23 and 24 may be pivoted to raise and lower the wheels I i by acting on the shaft I0, I provide the lever 2'! which is formed on the member 23 and extends rearwardly thereof for engagement by the operators foot. Each of the cam locking members 23 and 24 has the edge 218 thereof formed at a flat angle and the apex 29 of the angular surface edge 28 is the stopping point of the shaft 10 when the wheels 1 I are in raised position.

The lever 21 is adapted to extend outwardly of the housing It for foot engagement my means of the slot 30 formed in the housing I5 through To maintain the shaft l0 and the wheels H in a raised position I provide a spring 3i which is secured at 32 to the under side of the housing It and at 33 to the pivoted arm l3. To limit the extent of the downward movement of the wheels ll through the movement of the arms I3 and I3 I provide the stop member 34 which is secured to the underside of the gear housing l6 and acts in combination with the semi-circular portion 26 to place the lowered wheels in a positive secured position. With my new compact construction the wheels are easily enclosed within the rear portion of the housing It.

I also provide the resilient tubular members 35 and 36 which are secured on the shaft H! in such a position so that contact is made with the semicircular corner portion 2!] When the shaft 10 is raised thereby cushioning the upward movement of the shaft It).

In outlining the operation of my device we will assume the wheels H are in the raised position shown in Figure 4 where the shaft I0 is positioned against the apex 29 of the angle of the edge 28, the spring 3i holding the arm l3 in raised position and the resilient tubular members in contact with the portion Hi. In this position the upper edge of the lever 21 also engages the upper end of the slot 39. To lower the wheels I! the operator merely presses his foot on the lever 2! and pushes the same downwardly, and as this is done the shaft it travels from point 29 down the edge 28 a of the cam members 23 and'24 whereby the shaft 7 housing with regard to the position of the shaft 2 I above it. V

In th type of machine illustrated in Figure l the wheels are raised to allow the brush v3! to contact and operate on a floor to be treated. My invention provides a mechanism acting directly upon the shaft mounting the wheels of the machine which places-the wheels in a positive lowered or raised position by a simple movement of the foot. With the wheels in a positive lowered position the machine may be easily moved about with little or none of the surface of the brush contacting the floor. In raising the wheels II the lever '12? is raised and the shaft 10 is released from the notch 26, the shaft ll! traveling along the edge 28 to the point 29 where .it is held as hereinbefore set forth.

The invention'is not to be understood as restrictedto the details setforth since these may be modified within the scope of the appended claims without departing from the spirit and scope of the invention.

Having thus described the invention, what I claim as new and desire to secure by Letters Patent is:

.1. A wheel raising and lowering mechanism for a floor polishing machineincluding a wheel shaft,

a pair of arms secured to said shaft, means for pivoting said arms to the floor polishing machine, a pair of cam locking elongated arm members each having a semi-circular notch formed in the lower end thereof adapted to engage said wheel shaft and release therefrom, said cam arms being pivotally mounted at a point on said machine rearwardly of th pivot point of said wheel shaft arms, a lever secured to one of said cam arms to move said cam arms downwardly and forwardly against said wheel shaft, a flat angle edge formed on the forward edge of each of said cam arms adapted to slideably engage said wheel shaft as the same is raised or lowered, the apex ofsaid flat angle engageable with said wheel shaft when the wheels ar raised, spring means secured to said pivoted arms and adapted to be secured to the floor polishing machine whereby said pivoted arms are urged in an upward raised position.

2. A wheel raising and lowering mechanism for mobile units including a wheel shaft, a pair of 'armssecured to said wheel shaft, a pair of spaced apart cam arms each having notch means formed on the lower free end thereof adapted to releasably engage said shaft, a lever secured to one of said :cam arms, a second shaft secured to the upper ends of said cam arms and mounted at a pointrearwardly of said wheel shaft for pivoting said cam-arms, said second shaft being positioned slightly to the rear of thevertical center of said wheel shaft when the wheel shaft is in lowered position, means for mounting said shafts the housing of the mobile unit, and spring means secured to one of saidpair of shaft arms adapted to be secured to the housing of the mobile unit to maintain said shaftarms and said cam arms in a raised position.

3. In a wheel raising and loweringmechanism for floor treating machines and the like, a shaft for mounting a pair of wheels, arm means for pivoting said shaft to the floor treating machine, a pair of spaced apart elongated cam arm means having a notch formed in the lower end thereof for engagement with said wheel shaft, a shaft secured to said cam :arm means, means for piv- References Cited in the file of this patent UNITED STATES PATENTS Name Date McCarthy May 4,1915 Rey Jan. 26, 1943 Vavrik et a1 Nov. 16, 1943 Number a a an 

